QueryString.stringify() allowed a fourth argument that was used as a
conditional in the return value, but was undocumented, not used by core
and always was always false/undefiend. So the argument and conditional
have been removed.

Signed-off-by: Trevor Norris <trev.norris@gmail.com>

This reverts commit 95ee84fabe0b028ef964cc1032cd56a6cf89cb0e.

Increases the grep factor. Makes it easier to harmonize type checks
across the code base.

Binding of `http_parser` in querystring isn't used anywhere and should
be removed.